Method and apparatus for making an absorption control element



Oct 1951 w. R. KELLETT ETAL 2,569,765

METHOD AND APPARATUS FOR MAKING AN ABSORPTION CONTROL ELEMENT Original Filed April 4, 1946 5 Sheets$heet 1 was Oct 2, 1951 Original Filed April 4,

w. 'R. KELLETT ETAL 2,569,765 METHOD AND APPARATUS FOR MAKING AN ABSORPTION CONTROL ELEMENT 1.946 5 Sheets-Sheet '2 [n we 7222715:

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METHOD AND APPARATUS FOR MAKING AN ABSORPTION CONTROL ELEMENT Original Filed April 4, 1946 5 SheetsSheet 3 f 717/67Z2715 (Uri 22am R .51 2! Z ef Z and .50 u. is 6 VJ? Zea" 'oc z, 1951 w. R. KELLETT ETAL 2,569,765 METHOD AND APPARATUS FOR MAKING AN ABSORPTION CONTROL ELEMENT Original Filed April 4, 1946 5 Sheets-Sheet 1 1951 w. R. KELLETT ET AL 2,569,765 METHOD AND APPARATUS FOR MAKING AN ABSORPTION CONTROL ELEMENT Original Filed April 4, 1946 5 Sheets-Sheet 5 Patented Oct. 2, 1951 METHOD AND APPARATUS FOR MAKING AN' ABSORPTIONGONTROE -EIJEMENTn William'R; Kellett,Menasha, and Louis G. Veler, N eenah, Wis.,.assignors to International Cellu-q cotton Products Company, a corporation of Delaware Original" application=iApril 4;1946, Serial rNo; 659,542. Dividediand this application January 2, 1948, Serial No. 344

16 Claims. 1 This application is a division of our co-pending application Ser. No. 659,542, filedAprilA, 1946.

This inventionrelates to sanitary bandage or By absorption .control element we fluid which penetrates to the interiorof the -article in a restricted or localized area more or less corresponding to a restricted or.localized..sur-. face area: of the article toswhich fluid is .delivered.. The purpose of effecting such spreading is to cause more of the absorbingcapa-cityof the article :to be .utilized. than..has heretofore nor-.

mally been experienced The present invention has. forit main objects the productionof an improvedsanitary napkin,

and the production of anexceptionally effective absorption control element of. the character indi cated. Other objects are to provide a method forproducing the improved element with a mini-- mum of labor, at a low cost, and in sucha man-.

ner that the. product Will be hygienicallyclean,

and to provide. apparatus. which will. .advantae geously produce elements of the character indicated-according to the method preferred;

Other objects and advantages of'the-invention will be understood by reference to the following specification and accompanying drawings (five sheets) wherein a selected form of the invention is illustrated.

In the drawings,

Fig. 1 is a side elevation illustrating a selected mechanism for producing. the material of the improved absorption control element;

Fig. 1a is a diagrammatic illustration of a modification of part of "the mechanism shown in Fig. 1;

Fig. 2 is a diagrammatic side elevation of mechanism for further acting on the material produced by the mechanism of Fig. 1;

Fig. 3 is a plan of the apparatus shown in Fig. 1;

Fig. 4 is a section on the line 4-4 of Fig. l;

Fig. 5 is a section on the line 5-5 of Fig. 3;

Fig. 6 is a section on the-line 6-6 of Fig. 5;

Fig. 7 is a section onthe-line 1 -1 of Fig.1;

Fig. 8 is a more or less schematic section of a detail of the mechanism shown in Fig. .2;

Fig. 9 is a perspective illustrating the product in the form in which it is Wound into roll form by the mechanism shown in Fig.2 r

Fig; 10 is a perspective of "a single absorption spreading element embodyingthe invention, and

Fig. 11 is.partially aside elevation, and partial-l 1y a cross section through theimproved sanitary; napkin.

In the.manufactureofsanitary napkins, an absorbent pad unit is cut from a continuous web of the pad material; The ends of, the.pads are usually rounded 011' such rounding resulting;in the production of some waste pad material. These waste pieces may be utilized in the produc tidn .of new paper. but for that purpose they. have a relatively minor value.

According .to the present. invention, such waste). pieces of. pad. inaterialdwhether .lembodying a plurality. of relatively superposed plies of crepe tissue paper or abody of loosely .felted absorbent. fiber-like material usually. called fluff, or both, may be converted into material and'embodied. in webs or sheets from which the improved. absorption .control elements andfsanitaryinapkins may be cut. Suoh'waste .pieces jof materiaLmay be discharged byflth'e napkin-making machines into. ducts which deliver the pieces to a suitablecyclone or other collector. From such. collector the, pieces are "conveyed toa conduit I (Fig. l) i into. the upper end of a cyclone collector 2. The" pieces are ultimately delivered by the cyclone or withdrawn from the lower end of the cyclone, by a centrifugal blower ,3, the inletof whichis icon-.1 nected to the dis'chargeend of the cyclone 2 by a conduit 4. The dischargeside of the blower 3 has. connected to it a conduit 5 which asshown at 6 l (Fig. 4), passes through the Wall of a conduit 1 which is covered witnheat insulation 8. The conduit 5 continues within the conduit 8: and emerges from the latter as indicated at 9 (Fig l) By' jthis arrangement it will be seen that the waste material from the napkin producing machinery willbe'collectedand propelled in an airbornestreamthrough the conduit 5 which, for the greater portion of its length, is located within the insulated j conduit or casing 1. The arrangement issuch thatjan' airborne stream of fibrous materialflpieces which is substantially" constant in-its velocity and-in its fibrous material' content will be carried through'saidconduit5.

The fibrous material pieces passing. through the conduit 5 within the casing] are sized with suitable moisture resistant 1 sizing, such as wax of any suitable composition. One suitable composition of wax consists of "about 25 per centof a microcrystalline,.140 F'. melt wax' and per. cent refined F. melt paraflin. This mixture produces'asizingmaterial which is reasonably,

3 stable when applied to the fibrous material which is to be sized.

The wax mixture is sprayed into the air borne stream of' fibrous material pieces by means of either one of a pair of suitable spray heads II], Iii (Figs. and 6) which delivers its spray of molten or liquid wax through an opening II in an angular wall portion I2 formed in the conduit 5. There is one opening I I for each of the sprayers. The spray heads II], II] are supplied with compressed air through a suitable compressed air hose or pipe I3 located outside of the conduit 5 but inside of the casing I. Wax is supplied to the respective spray heads by means of hoses or pipes I4 and I5 through a suitable valve I6 which is controlled by a solenoid II.

Wax is delivered to the valve I6 by a supply pipe I8 which is connected with suitable pumping mechanism for delivering the wax under a predetermined pressure. It is preferable that the wax be pumped to the spray nozzles by means of a positive displacement gear pump (not shown) although any pump which will produce the desired steady flow of wax may be employed. Compressed air at from about 30 to 60 pounds per square inch pressure produces a satisfactory spray in the arrangement shown.

The conduit 5 is reduced somewhat in' cross section as it approaches the spray nozzle opening II, the u per wall portion 5a of the conduit in the bend immediately before the spray opening being arran ed in an eccentric relationship to the lower wall portion as represented in Fig. 5. This arran ement facilitates the provision of the angular wall I2 for the s ray openings II without producing any inwardly projecting obstruc- 7 tion in the conduit 5.

Pieces of fibrous material are indicated at I9 in Fig. 5. these pieces representing an air borne stream of such fibrous material pieces which emanate from the production of sanitary napkin pads as already explained. As the pieces I9 pass throu h the spray or fine shower of molten wax they become more or less completely coated with the wax and to some extent, impregnated with the same.

In order to prevent cooling and setting of wax on the conduit 5. it is heated by means of hot air delivered to 'the casing I from'a heater 20 (Fig. 4) throu h which air is blown by a suitable blower 2|. steam or any other suitable type of heater which has the reouired heating capacity. The hot air is recirculated. the end of the casing I from which the conduit emerges as shown at 9 in Fig.

1. being connected to a heat insulated return pipe 22 which is connected to the inlet end of the said blower 2 I. The blowers 3 and 2I may be driven by any suitable means not herein shown.

By thus heating the conduit 5 any heat liquefied sizing material will be kept in a liquefied condition so that the fibrous material pieces passing through the conduit will serve to wipe such liquid from the inside surface of thepipe as an incident to the passage of said stream of pieces through the pipe.

Th spray nozzle I0 may be housed in a chamber formed by a wall 23 and a removable cover 24 (Fig. 5). The wall 23 may form a part of the casing I and said wall i preferably provided with opening, such-as indicated at 25, to permit a limited amount of hot air to enter the housing of the nozzle I0 so as to maintain it at a temefliciently carried on.

The heater 20 may be an electric,

The wax delivery pipes I4, I5 and I8 and the compressed air pipe I3 are preferably located within the hot air jacket as shown to thereby aid in maintaining the sizing material at the desired spraying temperature. Means, not shown, are provided for automatically opening one spray nozzle in the event that one being used becomes material which enters the hammer mill is of'a fibrous nature, the disintegration of the pieces results in the reduction of the pieces to a more or less shredded or fibre-like form although not necessarily into individual fibers. The disintegrated material is fine enough that it may be deposited in a uniformly thick loosely felted layer. I

Instead of spraying the stream of waste material in the conduit 5 with the sizing material, the sizing material may be sprayed into the hammer mill. This arrangement would make unnecessary the heat jacketing of the conduit, but in such a modified arrangement the hammer mill, itself, should preferably be heated to a temperature well above the melting point of wax and to that end, the mill may be jacketed for heating and heat retention purposes.

In another arrangement, p-ieces'or sheets oi fibrous material may be run between one or more pairs of coating rolls which may be arranged to apply the desired sizing material on thesurfaces of the pieces or sheets which may then be fed directly to the hammer mill to be thereby disintegrated, or to means for first shredding the coated material and then to the hammer mill. The processing of the material in the hammer mill serves to effect distribution of the coating of sizing material to substantially all of the fibers while also disintegrating the pieces or sheets. A typical arrangement of this kind is illustrated in Fig. 1a wherein a web of paper pulp P is continuously advanced by variable speed feed rolls F, first between a heated roll H and a wax applying roll W and then into a hammer mill M, shredder or the like. Wax is supplied in measured quantity to the roll W by a knurled or etched roll E which rotates in a bath of molten wax S. The fiber material discharged from the mill M is preferably delivered by the blower B to an attrition mill,

hammer mill or the like for further breaking down the waxed board material and to additionally distribute the wax in the material. Such additional mill may be represented by the mill 25 in Fig. 1, from which the material is deliveredto bat forming apparatus. By heating the pulp board, the wax is caused to penetrate the board to a greater extent than if applied to the board at room temperature. Thorough distribution of the wax is thereby facilitated.

Another arrangement is to prepare sheets of beater sized pulp and to feed such sized pulp sheets directly or from shredding equipment or the like, to the hammer mill for reduction to flufi forming fiber form. In some instances, it

iiiayi be "desirable to pass thematerial"from-"the? first hanimer' mill to a second hammer mill to'redu the inaterial-tothe' desired degree of -fine- Sizing material other than wax may be 'used;

if desired?" For example, gum rosin or synthetic w resins ""may' be used and applied by whatever method is bestsuited to their particular=characteristics.

In the present arrangement the hammer mil-l is suitably supported on a frame structure- 2!- and driven froma source ofpowernotshownthrough the-"agency of apulley or the like; represented at 28. see Figs. 1 andfl). Themi-ll has a discharge opening-or outlet covered-by a screen-'29 (Figfl);

The screenmay be of suchsize that-onlyiibers of a predetermined" fineness wilt-pass through it fondelivery to the'loosely felted layer-formingmeansr A-screemof' about inch mesh gives a suitable type or fineness ofdisintegratedmaterial or-fluff: 'Incident to the disintegration of the pieces:offibrous-material, the hammen-mill screen 29 and is guided downwardly in aconduit 30-which is'of approximatelyrectangular for-m inf-cross section but which expands downwardly as'shown in Fig. 1.

A screen or other; pervious conveyor 3lis sup. portedonfa pair of rolls 32 and 33 which are suitably mounted for rotation, one or both of said.

rolls-being driven bymeans not shown. The speed atwhich the conveyor is driven may be variable sothat it may be caused to travel at a speed which will permit the fluff layer of'desired thickness; to be accumulated on the screen (or. ona tissue paper webdelivered to thescreen) incidentto the travel thereof under the lower end of the conduit 30'. A roll 34 of unsized crepetissue. paper 35*is uitab wr 5Q ih fl W b leerdelivered to the conveyor 3 I, a guide roll -36 being provided in juxtaposition'to said conveyor scr'eeii toposition the paper web on the face of said conveyors' V As shown in Fig.- 1, the upperreach of the conveyor travels to the right as indicated by the arrow, fluff represented at 31 descending andbeing deposited on the tissue paper web. A layer of such fluff will be accumulated on the tissue paperweb,

the. depthof the layer being-of course dependent upon the speed at which the .tissue paperweb traverses the dischargeend of the conduit fiil andthe volumeotfluff in the descending stream in' the conduit 30. At theoutlet sideof the div charge end of the conduit 30 there is provided-a rol l .38 which serves to more -or less smooth the top-of the fluff layer and to slightly compress "it. The rolls 36 and 38 may be driven by any suitable means (not shown) to avoid the creation of any resistance to the movement thereunder of the tissueweb and fluff layer respectively.-

To aidthe deposition-of the fluff'onthetissueweb inits passage under the end of the conduit 4! which serves to create more or less of a vacuum in said suction box to thereby pull" the material into more or Jess-intimate engagement with-the tissue "web 35and the particles of fluffmaterial-into more or less intimate engagement with each-other. I. This suctioninduced intimate engagement of the fibers with each other effects light inter-attachment between the engaging fibers and said-suctioninduced engagement of l the fibers withthe tissue backing sheet; and also,

the pressure applied bythe roll 38, effects light interattachment ofsaid fibers to said backing sheetr The sizing material carried bythe fibers:

whenbf an' ad-hesive characteristic, may also aid in 'efiectingsaid-fiber to sheet interattachment.

To controlthesuction effect at various trans--. verse sections of the conveyor, the suction box l is 'advantageouslydivided into a plurality of longitudinallyextendingpartitions such as indicated at42""(F'ig."7), the outlet ends of which the-channels in all positions of the dampers Another roll M ofunsized crepe-tissue paper- "is suitably supported near the outlet side of the 'conduitiifi and the web 45 of that roll isguided into superposed relation to the fluff layerby means of a suitably mounted guide roll -46.-

The guide'roll 43 may be driven, if desired, to avoid any'resistance tothepassage of the -tis-- sue 45 or to'aidin the -feed'of the tissue 45 intoplace on the fluff layer. resented at 41 in Fig. 1. l

The sandwich 'thus formed comprising top and bottom" tissue paper webs- -and'an intervening-5' layer "of loosely felted pulp is then preferably rolled up into a roll 43 by suitable winding mechanism, such as represented at" 49.-" The winding-:-

mechanism 49"maybe of any known form. and is more or lessdiagra'mmatically represented by "therolls 49.

The roll 48 maybe removed from the winding? mechanism 49 and delivered to supporting means, such'as represented at 50 of an embossingx" h machine 5i which" next acts'on the composite bat of'm'aterial to interconnect the tissue 'webs andflufflayer to form a unitary structure frame! The-embossing machine 5| embodies upperand lower rolls" 5 2"and 53"respectively of which thelower 'i'oll 53 may have a smooth surface 54 showmin Fig. 8, andthe upper roll a longitudina-lly' grooved or fluted surface providingup stahdi'ilgribs 55: The bat of material representedat 56 is guided between these rolls with the. result that the bat is highly compressed par ticularly in the areas engaged by the surfaces of "the ribs 55 The roll 53 alone may be posi- The roll" 52 maybe urged against the roll 53 un dera pressure 'on'the order of'abo'ut 1100 pounds peri inchof nip that is to say, 1100 pounds: per incli'of roll length, such pressure beingsufficient to consolidate the fibers of the top and bottom tissues and the intervening layerof surf to such"? an extent that the parts become'errcuvuyzf united.-

The ribs 55 of the embossingroll 52 arepref-I erably-in the form of herringbone ribs; that is l to say,;;the opposite halves of the ribs are ar-' ranged at complementary angles sothat there; will;at-a1l-times;be contact between a rib of -the] roll 52 and the roll 53-thereby avoiding. any

"'bumping efiect which might occur if theribs were disposed in parallel relation to the axis of.

width and for winding the strips into rolls. Such slitting and winding mechanism is represented diagrammatically at 58 (Fig. 2), the embossed .web being guided around a roll 59 against which one or more slitters, such as represented at 60, act to slit the bat into strips of the required width. From the guide roll 59 the strips are guided properly to winding mechanism which is here represented as comprising a pair of driven rolls-6l. The winding mechanism may, of course, be" of any suitable character and is merely diagrammatically represented by the roll Bl.

The slitted embossed web is more or less diagrammatically represented in Fig. 9 wherein the width of the web is represented as being slit into six strips by suitably spaced slits 62. Each of the strips 63 thus formed will, of course, be rolled into its own roll by the winder 6 I.

In the production of sanitary napkins, a rolled strip- 63 will be suitably mounted so that the strip may be fed from the roll into sandwich position between other parts of the sanitary napkin pad and from the resulting composite structure portions of the required pad width will be cutin accordance with known practice.

The absorption control element produced and embodied in a sanitary napkin by the said means, is represented alone in Fig. 10 wherein the length L of the element corresponds to the width L of the'strip 63 and the width W of the element corresponds to the width of the sanitary napkin pad produced.

The control element 64 thus produced comprises top and bottom crepe tissue paper'members and an intervening layer of sized fluff. The sizing in the fluff is quite uniformly distributed so that the fluff is effective to resist penetration by moisture'for a considerable length of time and until the absorbent materialon one side of the element as in a sanitary napkin is well loaded and has lost most of its capacity to absorb fluid. The control element produced in accordance with this invention thus acts somewhat in the nature of a bafile. However, the creping in the tissue paper covers of the element, and the highly compressed longitudinally extending zones in the unsized cover plies of the element provide a degree of accelerated capillary action which also tends to spread the area of absorption. The described element is highly effective in a sanitary napkin to prevent so-called strike through, i. e. the passage of absorbed fluids directly from one side of the napkin to the other, and is thus a highly advantageous construction.

In the production of the element it would, or course, be possible to direct the composite pad directly from between the roll 46 and the conveyor screen 3| (Fig. 1) to the embossing mechanism, but for practical purposes it is preferred to wind up the composite bat and to transfer rolls thereof to the embossing machine. As a practical matter, the speed at which the composite bat is formed by the apparatus shown in Fig. 1 isconsiderably less than the speed at which the embossing mechanism may advantageously be run. Hence, the embossing machine need be operated only intermittently to emboss the composite bat produced by a single unit of mechanism, such as shown in Fig. l.

H Asanitary bandage embodying the improved absorption control element is illustrated in. Fig. 11. It comprises the absorption controlelement 64 disposed intermediate layers or plies 65 or 66.

of absorbent fluff material. These layers of fiufl.

material comprise: amultiplicity of. absorbent cellulose fibers arranged in haphazard relationship to produce a very soft absorbentmass which,

because of the haphazard arrangement of the. fibers, has no predominant grain or other char-r acteristic which would direct the spread offluid absorption predominantly in any one direction.

The fluff material is quite similar to the fluff material which enters into the construction of H the absorption control element but it is, of course, not sized. Outside of the fluff layers 65 and B6, there are layers 61 and 68 respectively of absorbent crepe tissue paper, these layers each comprising a plurality of plies of crepe tissue paper preferably arranged with the lines of creping extending lengthwise of the napkin, this being also true of the direction of creping in the crepe tissue paper cover plies of the absorption control element 64.

The crepe tissue layers 61 and 38 extend endwisebeyond the opposite ends of the fluff layers 65 and 66 and have their opposite ends united by means of pressure as indicated at 69 in accordance with the teaching of Reissue Patent No. 21,076 to Glomstead, May 9, 1939.

The usual gauze jacket is applied to the absorbent pad, such gauze jacket being represented at 10, the same having a single ply over the top surface of the pad, and two plies over at least a portion of the bottom surface incident tothe overlapping of marginal portions of the gauze jacket which is formed of a sheet of gauze wrapped transversely around the pad. The gauze jacket extends beyond the ends of the absorbent pad body to form the usual attachment tabs.

In a sanitary bandage, fluid deposited in some localized area on one face of the pad quite readily penetrates the gauze jacket and the tissue and fluff layers of the pad on the side thereof on which the fluid is deposited. The crepe tissue layer, such as 61, has a desirable tendency to spread the area of fluid absorption lengthwise of a the pad from the localized area of fluid deposition, but that tendency is not strong enough" to' prevent a part of the fluid from penetrating towards the interior of the pad and towards the opposite side thereof especially in a limited or localized area in which fluid may initially be deposited on the bandage. However, when the fluid strikes the sized core of the control element 64 its further passage toward the opposite side of the pad is resisted and this resistance is strong enough to cause the fluid to spread laterally within the pad. Lateral spreading of fluid within the pad is promoted in the direction of the length of the pad by the direction of creping in the affected cover of the control element and by the elongated compressed zones of the cover sheet, the latter spreading action being in the nature of the action provided by the so-called' equalizer unit shown in Heitmeyer Patent 1,863,-

333. The sized material in the core of the control element thus contributes materially toward the equalizing effect 'of the compressed zones and this so-called equalizing effect may, within certain practical limits, be amplified by adding additional unsized tissue plies to the surface of the control element.

not produce an impervious bafiie but instead con-' stitutes a permeable core through which the 1 9 nabsorbedicfluid: may ultimately penetrate. Such .wpenetration will occur after the. absorbent layers, in suchas fi'l and 65on one side of the. control ele- "am'ent, havewbecomefairlywell loaded with abe s'orbed fluid so that the fluid pressure exerted on the control. element becomes great enoughto cause penetration of the control element. The absorbent layers, such as 66 andiifi onithe oppo- --:site side ofthe pad, may then take up additional fiu-id delivered to the pad in said localized. area but absorption will then usuallyoccur over a -major portionpif not all-of the area of rcontact between the control element andtheabsorbent ayer 66. This follows from thefact that a corresponding" area of the initially Wetted. side of ere pad is Well loaded with fluid and tends to efiect penetration of the control-element over a correspondingly well spread area as distinguished from the localized area of fluid application.

{In some instances,penetration of the control baffle may be completed in a concentrated or localized area due perhaps to extreme wetness "0f-the initially wetted side of the pad in such an area. In such acase', the control element cover sheet on thelower or then dry side of the pad will--p pmote spreading of the penetrating fluid r-from such localized area in about the same manner as above explained in respect of the action of the other cover sheet. Hence, the last wetted cover sheet serves as a safety measure to insure fi-uid delivery to a major-portion of the area of the -lowermost or outermost layer of fiuif absorbent 'material. Furthermore, if the bandage is kept in use for such an extended period that the absorbed -fiu'id actually reaches'the remaining tissue layer, saidremaining tissue layer will also tend to insure distribution of the fluid throughout the area of the pad.

Various changes may be made in the described structures and arrangements without departing from the spirit of the inventionas set forth in i the appended claims in which some of the speciifled elements and steps of procedure may be re- ---placed by equivalent elements and steps without departing from the invention.

*We claim:

1. The steps in method of making an absorp- ,tion control element of the class described, which comprises theLsteps of disintegrating a body of fibrous materialin the presence of a sizing agent oflmoisture resistantmaterial to fiber-like shred -form, whereby saidsizing agent is distributed to substantially all of said fiber-like shreds, and depositing said shreds in a layer of predetermined thickness on a Web of absorbent sheet material, .'thereby to form an absorbent sheet-backed bat of loosely felted, haphazardly arranged sized fibers havin thecharacteristic of being penetrable by fluid when subjected to a heavyioad .,thereof but resisting such, penetration, under .lighter' fluid loads.

2. .The steps in method of making an absorption control element of the class described, which com- ,prises the steps of disintegrating a body of fibrous nmaterialin the presence of a sizing agent of .,-moisture resistant material. to fiber-like shred f,orm, whereby said sizing agent is distributed bto substantially all of.,saidfiber-Iikeshreds, and depositing said shreds in a layer of predetermined thickness on a web of absorbent sheet material having the characteristic of accelerating the flow of absorbed fluids in a predetermined direction, thereby to form an absorbent sheet-backed bat of loosely felted, haphazardly arranged fibers having the characteristic of being penetrable by filbflllid'cwhefl subjectedto a heavy loadthereof but wresisting; such; penetration under lighter fluid u loads; andw which -bat,;,the backing sheet, is adapted to initially receive fluid to effect spread- 5-;.:ing otthasamei over an extended. area tothereby w retard-accumulation-ofthe fluid in alocalized iarea and establishment of heavyhfluid loadion a; localized ,area: of .said layerof fibers. i .3.-. T-hemethod of makingan absorption-control; element ,of the ,class; described which com- 3 prises, theisteps of applying sizin omateriali to ;1,.pieces.of fibrousmaterial reducing the pieces to .rfiben-likesshreds depositing said shreds haphaz- ...ardly ,in alaysen on arweb ofitissue papenandcovl5r-,eri ngthe layer. with a web .of tissue. paper. to .con-

. finesaidlayerbetween said webs.

4. Thamethod bf making" an absorption, con- .-,trol element. of. the bless described, which .com-

,priseswthe .steps of spraying sizingmateriaLon a 20., moving. stream ,of.. pieces ,of fibrous material, ,re-

,..,ducing therpisces to fiberelikeshreds, depositing .,.,said shreds ,haphazardlydn a layer on aweh of tissue paper, ,and coveringthe layerwith a web a, of ,tissue, papercto, confine said layer. between said webs.

, 5.. .Thelmethod ,of., making. an. absorption, con- ,...tr.01,..e1ement,oflthe, class described, 'Which, com- ,i prises ,the stepslof spraying. sizin material qnan air.,bornestream of. .,pieces, of .fibrous material,

30,, reducing the piecestofiben-like shreds, depositing "ssaidshreds haphazardlyin a, layenon a web of ntissue paper, and, covering the layer with a web of, tissuapaper toconfine said layer betweensaid ,6. The method, ,of makingan. absorption ,con- ,trol elementpf the class described, which comprises the steps of applying ,sizing, material to pieces of fibrous material, reducingthe pieces to fiberlike shreds, depositiong said shreds ..hap-

hazardly in a layeron a ,web .of.tissue paper, coverillgthe layenwithaweb of tissue paper to conline said layer between said webs,and applying pressure tospacedportions ofthe assembled layer ,rand tissue paper webs ,to, in .effect,consolidate the fibers of saidlayer and Webs. in said spaced portions to therebyv unite said layer and webs to each .other.

.7. The method of making an absorption control ,,element otthe class described, which comprises the steps of. producing an, air borne stream, of

pieces ,of fibrousmaterialinwhich the volume of ,said pieces, is rairly uniform at all times, spraying sizing material ,on the pieces flowing in said stream, delivering the stream to amill whichpp- ,erates ,to break. the piecesinto fiber-like shreds which will pass through a screen o f predetermined ,mesh, pneumatically effecting deposition of ,the

shreds in a substantially uniformly thickleyer on a moving, web ,oftissue, paper, and.covermg the layer with another web of tissue paper.

S Apparatus orthe class described, comprising a, collector, for,..fibrous,.,material, pieces, ear-- ried inan air stream, a conduit, means, for withdrawing saidf fibrous material pieces .from,,said

collectonand discharging, the same in an air bornestream into said conduit, means forspraying sizing. material into said conduit so, as to ,.deposit,,some, ,of said sizing material ,on said, air

' borne pieces, means for receiving'the stream 'of sized pieces from said conduit and provided with means for disintegrating said pieces into shreds, a pervious conveyor, means for guiding a web of pervious tissue paper into place on said conveyor, suction means for causing said shreds to be deposited on said conveyor borne paper web to thereby produce a layer of saids hredson saidweb, and means for applying a tissue paper cover sheet to the top side of said layer of shredded material.

9. App'aratuf' of the class described, comprising a collector for fibrous material pieces carried man air stream, a conduit, means for withdrawing said fibrous material pieces from said collector and discharging the same in an air borne stream into said conduit, means for spraying sizing material into said conduit so as to deposit some of said sizing material on said air borne pieces, a hammer mill for receiving the stream of sized pieces from said conduit and operative to disintegrate said pieces into shredlike pieces, said mill being provided with a screened outlet for discharging shreds of a predetermined maximum size, a pervious conveyor,

means for guiding a web of pervious tissue paper I into place on said conveyor, suction means for causing said shreds to be deposited on said. conveyor borne paper web to thereby produce a layer 7. of said shreds on said web, and means for, ap-

plying a tissue paper cover sheet to the top side of. said layer of shredded material.

, 10. The method of making an absorption control element of the class described, which comprises the, steps of applying sizing material to the surface of matted fibrous material, reducing the surface sized material to fiber-like shreds and agitating the shredsso as to effect transfer of some of the sizing material from the initially of some of the sizing material from the initially coated portions to a substantial portion of the fibers initially untouched by the applied sizing, depositing said shreds haphazardly in av layer on a web of absorbent tissue paper, and covering, the layer with a web of absorbent tissue paper to confine said layer between said webs.

12. Apparatus of the class described, comprising a collector for fibrous material pieces carried in an air stream, a conduit, means for withdrawing said, fibrous material pieces from said collector and discharging the same in an air borne stream into said conduit, means for spraying sizing material into said conduit so as to deposit some of said sizing material on said air borne pieces, means for receiving the stream of sized pieces from said conduit and provided with means for disintegrating said pieces into shreds,

' .a pervious conveyor, means for guiding a web of pervious tissue paper into place on said conveyor, suction means for causing said shreds to be deposited on said conveyor borne paper web 1 to thereby produce a layer of said shreds on said web, said suction means comprising a plurality of separated passageways extending longitu'dinally of said conveyor and dampers in each of said passageways for facilitating control of the suction applied to the respectively overlying conveyor portions, and means for applying a tissue paper cover sheet to the top side of said layer of shredded material.

13. The method of making an absorption control element of the class described, which comprises the steps of applying sizing material to pieces of fibrous material, reducing the sized pieces to fiber-like shreds, and depositing said fiber-like shreds in a layer to a predetermined depth, thereby forming a web of sized fiber-like shreds, the sizing material being distributed to said shreds from the sizing carried by the pieces and as an incident to the reduction of the pieces to fiber-like shreds. v

14. The method of making an absorption control element of the class described, which comprises the steps of applying sizing material'to the surface of matted fibrous material, reducing the surface'sized material to fiber-like shreds and agitating the shreds so as to eiiect transfer of some of the sizing material from the surface carried sizing material to a substantial portion of the'fibers initially located .inwardly of the surface of said matted material, and depositing the shreds which are sized as aforesaid in layer form to the desired depth.

15. The method of making an absorption control element of the class described, which comprises the steps of providing a flowing stream of surface sized pieces of fibrous material in which the volume of said pieces is approximately constant, delivering said stream of pieces to a mill which operates to reduce the pieces to shreds of predetermined fineness, and effecting deposition of said shreds in a layer of predetermined depth.

16. Apparatus of the class described comprising a conduit for-guiding an air-borne stream of pieces of fibrous material, means for spraying sizing into said conduit so as to deposit some of said sizing on surfaces of said air-borne pieces, means for receiving the stream of sized pieces from said conduit and disintegrating said pieces into shreds, a pervious conveyor, and pneumatic means for causing said shreds to be deposited on said conveyor to form said shreds into a layer of predetermined depth.

WILLIAM R. KELLETT. LOUIS G. VELER.

REFERENCES CITED The following references are of record in the file of this patent:

V UNITED s'rA'rEs PATENTS Number Name Date 1,941,255 Fourness Dec. 26, 1933 1,961,272 Williams June 5, 1934 1,970,742 Gerard et a1. -1 Aug. 21, 1934 2,023,273 Leguillon Dec. 3, 1935 2,057,166 Schur Oct. 13, 1936 2,086,592 Williams July 13, 1937 2,114,377 Goss Apr. 19, 1938 2,152,901 Manning Apr. 4,1939 2,262,275

Fourne'ss et al Nov. 11, 1941 

